function [newpath] = drive_subst(oldpath)
% drive_subst - substitute a new drive letter for the one currently in the path
h3=findobj('Tag', 'Drive');
if(ishandle(h3))
   dnum = get(h3, 'Value');
   drive = sprintf('%1s',char(dnum+64));
   [drv, nondrive] = strtok(oldpath, ':');
%   drv
   newpath = strcat(drive, nondrive);
  end
return;


 
